Many confidently -- even eagerly -- predicted catastrophes are late in arriving. There is a lengthening list of traumas to the planet that were supposed to have happened but haven't. This is one reason to be unimpressed by the "Earth Summit" in Rio.
The Audubon Society calls that summit "the most important meeting in the history of mankind." (So much for the Council of Trent, the Congress of Vienna and the first meeting of Plato and Socrates.) But any time agents of 160 governments gather, remember: Some Third World governments (which are most of the world's governments) are "kleptocracies." They would rather redistribute the First World's wealth than abandon the statism that is the basis of their power.
Some environmentalists (usually at comfortably endowed universities in developed countries) dislike economic growth, and many environmental measures hinder it. But growth is a prerequisite for environmental improvement. The worldwide pattern is that environmental damage increases until per capita income reaches a point where people enjoy a social surplus and feel they can ask government to trade some growth for environmental healing.
So before we are stampeded into growth-inhibiting actions to combat global warming, we should recall that less than 20 years ago -- not long in a planet's life -- the politically correct panic concerned global cooling. Then there were "many signs pointing to the possibility that the Earth may be heading for another ice age" (New York Times, Aug. 14, 1975), heading "toward extensive Northern Hemisphere glaciation" (Science magazine, Dec. 10, 1976), and facing "continued rapid cooling of the Earth" (Global Ecology, 1971) and "the approach of a full-blown 10,000-year ice age" (Science, March 1, 1975).
The Christian Science Monitor reported (Aug. 27, 1974) that armadillos had left Nebraska, retreating south, and heat-loving snails had retreated from central European forests, and "the North Atlantic is cooling down about as fast as an ocean can cool," glaciers "have begun to advance" and "growing seasons in England and Scandinavia are getting shorter."
Nowadays Newsweek's Greg Easterbrook, writing in Washington Monthly, offers his "Law of Doomsaying:" Predict catastrophe no later than 10 years hence but no sooner than five years away -- soon enough to terrify but far enough off that people will forget if you are wrong. Mr. Easterbrook has not forgotten Stanford's infallibly wrong Paul Ehrlich, who in 1968 said, "The battle to feed humanity is already lost. . . . We will not be able to prevent large-scale famines in the next decade." Since 1968 world grain production has increased 60 percent. For 30 years world excess food stocks relative to consumption have grown faster than population.
In 1980 Mr. Ehrlich bet economist Julian Simon $1,000 that in a decade the prices of five resources (copper, chrome, nickel, tin, tungsten) would rise. The prices of all five fell. Mr. Ehrlich paid. And Stephen Moore of the Cato Institute reports that, contrary to predictions that increased population and industrialism would produce scarcities, "by every objective measure natural resources became more, not less plentiful in the 1980s."
Indeed, "many environmentalists now complain of the ecological damage that will be done by cheap and accessible energy," Mr. Moore says. Measured in terms of the time a person must work to purchase them, natural resources are, on average, 20 percent cheaper than in 1980, half as costly as in 1950 and five times less costly than in 1900.
Eco-pessimism persists, more solid than environmental science, in part because it serves a political program. Some environmentalism is a "green tree with red roots." It is the socialist dream -- ascetic lives closely regulated by a vanguard of bossy visionaries -- dressed up as compassion for the planet.
Various reasons for gloominess come and go (dioxin and acid rain have recently been demoted as menaces) but the supply of gloominess is remarkably constant. A recent Science magazine editorial, "The Attractiveness of Gloom," satirically offered a new version of Murphy's Law: "Things are worse than they can possibly be." It quotes a fictional Dr. Noitall, who says his fellow gloommongers are handicapped by the fact that standards of living, and life expectancy, keep rising. However, he takes comfort from the fact that anxiety will remain high because "expectations always increase more rapidly than productivity."
And he contentedly anticipates "the panic that will spread through the population when they read about the epidemic of deaths through natural causes." You read about it first here.
George Will is a syndicated columnist.